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fiziko writes in with a self-described "blatant self-promotion" of a worthwhile service for those wishing to go beyond Khan Academy physics: namely Bureau 42's Summer School. "As those who subscribe to the 'Sci-Fi News' slashbox may know, Bureau 42 has launched its first Summer School. This year we're doing a nine-part series (every Monday in July and August) taking readers from high school physics to graduate level physics, with no particular mathematical background required. Follow the link for part 1."

This is good advice, and gives me an opportunity to speak to the community at large: some of us who go to cons and are in a position to shake tons of hands politely decline. It's not because we're being dicks, it's because we know it's a good way to substantially decrease our chances of catching and spreading any germs.

I played the PAX Pandemic game, where the Enforcers handed out stickers to attendees that read [Carrier] [Infected] or [Immune] (There was also a [Patient Zero].

I got the [Immune] sticker, and by the time I got home on Monday, it was clear that I had the flu. I've had a fever between 100 and 104 all week that finally broke last night, but I'm going to the doctor today because I think whatever I had settled into my lungs. I'll tell him about the H1N1 outbreak and get tested if he wants to run the test, but at this point I think it's safe to assume that I was [Immune] to the Pig Plague, but definitely [Infected] with the damn PAX pox.

Even though it's been a week of misery, it was entirely worth it, and I don't regret going to PAX for a single second.

Hydrogen peroxide powered rocket packs fly for around 30 seconds, because they have a specific impulse of around 125, meaning that one pound of propellant can make 125 pound-seconds of thrust, meaning that it takes about two pounds of propellant for every second you are in the air. Mass ratios are low for anything strapped to a human, so the exponential nature of the rocket equation can be safely ignored.

A pretty hot (both literally and figuratively) bipropellant rocket could manage about twice the specific impulse, and you could carry somewhat heavier tanks, but two minutes of flight on a rocket pack is probably about the upper limit with conventional propellants.

However, an actual jet pack that used atmospheric oxygen could have an Isp ten times higher, allowing theoretical flights of fifteen minutes or so. Here, it really is a matter of technical development, since jet engines have thrust to weight ratios too low to make it practical. There is movement on this technical front, but it will still take a while.

John Scalzi wrote a hilarious exchange on his blog the sums up perfectly why this idea is made of fail:

Sony BMG spokesperson: We're pleased to announce we are the final major music corporation to release electronic tracks without that pesky DRM! All you have to do is leave your house, go to a selected retail outlet, buy a special card there, go back to your house, scratch off the back of the card to find a code, go to our special MusicPass Web site, enter said code, and download one the 37 titles we have available, from Celine Dion to the Backstreet Boys!

Kid #1: Or, in the time it takes me to jump through all those hoops, I could just download all 37 of those albums off of Pirate Bay.

Kid #2: Or, I could just scratch off the back at the store, record the pin number, go home and download the album through a Tor connection, so you can't trace my IP number.

MrCrassic writes "It appears that Google is initiating talks with well-known PDA/smartphone manufacturer HTC to make the Google phone a reality. With impressive tech specs and an already impressive concept underway , could Google be the next company to make a mark in the wireless device industry?
From the main article:

However, a recent report by CrunchGear states that its own sources at mobile handset provider HTC have tipped the site off to multiple gPhone handsets being prepped for launch in the first quarter of 2008 and that the handsets will be coming out of Taiwan. There will supposedly be over 20 different handsets to choose from — some with GPS — and they will carry special versions of Google Maps, Google Calendar, Gmail, and VoIP-enabled Google Talk.
Speaking of software, Google is rumored to be developing its own operating system for the gPhone. According to reports by Engadget, the OS has been in development since 2005 after Google's acquisition of a mobile software company called Android. The Android team has since developed a Linux-based mobile OS while at Google — a detail that is corroborated by the CrunchGear report — which of course comes with tight Google integration. Both sites appear to agree that their sources indicate Google isn't currently looking to develop the hardware... for now.

In response to yesterday's casting news about Chris Pine possibly taking the captain's chair for the new Star Trek movie, apparently Simon Pegg will be playing the role of Scotty. Simon Pegg is known for his role as Shaun in Shaun of the Dead and more recently for his leading role in Hot Fuzz. "Pegg joins Zoe Saldana as Uhura, Anton Yelchin as Chekov, John Cho as Sulu and Zachary Quinto as Spock in the film which reportedly, and logically, 'chronicles the early days of the Enterprise crew.' Leonard Nimoy will also put in an appearance, while Eric Bana signed up this week as the movie's villain, Nero."

The Scientist reports that UK group Sense About Science is confronting advertisers about pseudoscientific claims in health products such as "Aerobic Oxygen," "Salt Lamps," and "Activ8." They called the advertisers' customer service numbers and grilled the unfortunates on the other end of the phone about their misuse of scientific language to sell products. The project,

OK. I can't give you the code but it is my own implementation of a pretty standard bioinformatics sequence comparison program which doesn't use SSE/MMX type instructions and is single threaded. On all platforms it was compiled using gcc with -O3 optimisation. I have tried adding other optimisations but it doesn't really make much difference to these numbers (no more than a couple of percent at best).

When you say you've tried "adding other optimizations," are you referring only to other GCC optimization flags? If your program's algorithms have any moderate degree of parallelism and you haven't tried vectorization either by compiler (GCC and ICC can both do this) or by hand, the benchmark you've done is not unlike a race where no one is allowed to shift out of first gear. Can you go into any more specifics about how this program does sequence comparisons?

Also, the disappointing numbers from the G5 may be partially explained by the fact that its integer unit has higher latency than the other desktop processors in that list. The G5 isn't exactly known for blistering integer performance, anyway.

For the last year or so, I've been happily using Debian, with a mixture of sources so I was stable, but current, just like nearly everyone who uses Debian.

Then I tried to upgrade or something insane like that, using aptitude, and the whole thing went tits up on me. No amount of cussing, kicking things, or actual tinkering with the software could save my machine.